Periodic nulling and even-odd modulation properties of PSR J2313+4253
Amplitude modulation of subpulses has substantial research implications for elucidating the geometric structure and emis-sion process of pulsars.Previous studies have revealed that the single-pulse sequence of PSR J2313+4253 exhibits am-plitude modulation with periodicities of 44 and 2 rotation periods.Moreover,shorter periodicity is associated with the even-odd modulation phenomenon,but its physical origin is unclear.We performed a detailed study of individual-pulse emission properties from the pulsar J2313+4253,observed at 2250 MHz using the Jiamusi 66 m radio telescope in this study.Using longitude-resolved,harmonic-resolved and two-dimensional fluctuation spectral techniques,we find that the even-odd modulation originates from short-period subpulse drifting,which exhibits considerable temporal dependence.The analysis reveals that the even-odd modulation phenomenon may be attributed to the aliasing effect caused by overlap-ping sub-beams within the radiation zone due to unclear boundaries during the sparking discharge process in the pulsar magnetosphere.